Mixer for short mixing lengths

Patent metadata

Field	Value
Publication number	US-9447717-B2
Application number	US-201414540056-A
Country	US
Kind code	B2
Filing date	Nov 13, 2014
Priority date	Aug 21, 2014
Publication date	Sep 20, 2016
Grant date	Sep 20, 2016

Abstract

A mixer for an exhaust gas treatment system includes a support body that defines a mixing chamber. A plurality of first blades is arranged in a row, and is disposed along a transverse axis. Each of the first blades extends from an upstream edge, toward a first lateral edge surface of the mixing chamber, to a downstream edge, at a first row angle relative to the transverse axis. A plurality of second blades is arranged in a row, and is disposed along the transverse axis. Each of the second blades extends from an upstream edge, toward a second lateral edge surface of the mixing chamber, to a downstream edge, at a second row angle relative to the transverse axis. The first row angle is less than the second row angle. The row of the first blades is axially spaced from the row of the second blades.

First claim

The invention claimed is:

1. A mixer for an exhaust gas treatment system of a vehicle, the mixer comprising:
a support body defining a substantially rectangular mixing chamber with a fluid flow path disposed along a longitudinal axis, wherein the mixing chamber includes a lower surface, an upper surface spaced from and opposing the lower surface, a first lateral edge surface extending between the lower surface and the upper surface, and a second lateral edge surface extending between the lower surface and the upper surface and opposing the first lateral edge surface;
a plurality of first blades arranged in a single row and extending between the lower surface and the upper surface of the mixing chamber, with the single row of the first blades disposed along a transverse axis that is substantially perpendicular to the longitudinal axis;
wherein each of the first blades extends along the longitudinal axis, from an upstream edge, toward the first lateral edge surface of the mixing chamber, to a downstream edge, at a first row angle relative to the transverse axis;
a plurality of second blades arranged in a single row and extending between the lower surface and the upper surface of the mixing chamber, with the single row of the second blades disposed along the transverse axis;
wherein each of the second blades extends along the longitudinal axis, from an upstream edge, toward the second lateral edge surface of the mixing chamber, to a downstream edge, at a second row angle relative to the transverse axis;
wherein the single row of the first blades is axially spaced along the longitudinal axis from the single row of the second blades a row spacing distance;
wherein the first row angle is different from the second row angle; and
wherein each adjacent pair of the plurality of first blades are spaced a first gap distance from each other along the transverse axis, and each adjacent pair of the plurality of second blades are spaced a second gap distance from each other along the transverse axis, wherein the first gap distance is less than the second gap distance.

2. The mixer set forth in claim 1 wherein the row spacing distance is greater than 5 mm.

3. The mixer set forth in claim 1 wherein the first row angle is less than the second row angle.

4. The mixer set forth in claim 1 wherein the downstream edge of one of the plurality of first blades is substantially aligned along the transverse axis with the upstream edge of one of the plurality of second blades, an approximately equal distance from the longitudinal axis.

5. The mixer set forth in claim 1 wherein each of the plurality of first blades is arranged such that a line extending from the upstream edge to the downstream edge of each respective first blade forms an open side angle relative to the transverse axis and the first row angle relative to the transverse axis, wherein the open side angle and the first row angle are supplementary angles, the open side angle is an obtuse angle, and the first row angle is an acute angle.

6. The mixer set forth in claim 5 wherein each of the plurality of second blades is arranged such that a line extending from the upstream edge to the downstream edge of each respective second blade forms an open side angle relative to the transverse axis and the second row angle relative to the transverse axis, wherein the open side angle and the second row angle are supplementary angles, the open side angle is an obtuse angle, and the second row angle is an acute angle.

7. The mixer set forth in claim 5 wherein the first row angle between the transverse axis and each respective first blade opens in a first axial direction along the transverse axis, the second row angle between the transverse axis and each respective second blade opens in a second axial direction along the transverse axis, with the first axial direction opposite the second axial direction.

8. The mixer set forth in claim 1 wherein the first row angle is between 35° and 60°, and the second row angle is between 35° and 60°.

9. The mixer set forth in claim 8 wherein the first row angle is equal to 45°, and the second row angle is equal to 50°.

10. The mixer set forth in claim 1 wherein each of the plurality of first blades include a first blade length measured between the upstream edge and the downstream edge of each respective first blade, and each of the plurality of second blades include a second blade length measured between the upstream edge and the downstream edge of each respective second blade, wherein the first blade length is less than the second blade length.

11. The mixer set forth in claim 10 wherein the first blade length is between 5 mm and 15 mm, and the second blade length is between 20 mm and 30 mm.

12. The mixer set forth in claim 11 wherein the first blade length is equal to 12 mm, and the second blade length is equal to 24 mm.

13. The mixer set forth in claim 1 wherein the first gap distance is between 5 mm and 15 mm, and the second gap distance is between 10 mm and 20 mm.

14. The mixer set forth in claim 13 wherein the first gap distance is equal to 12 mm, and the second gap distance is equal to 14 mm.

15. An exhaust gas treatment system for treating a flow of exhaust gas from an engine of a vehicle, the exhaust gas treatment system comprising:
a flow structure defining a fluid flow path for the flow of exhaust gas;
a Selective Catalytic Reduction (SCR) catalytic converter in fluid communication with the fluid flow path for receiving the flow of exhaust gas;
an injector in fluid communication with the fluid flow path upstream of the SCR catalytic converter, and operable to inject a reductant into the flow of exhaust gas;
a mixer disposed downstream of the injector and upstream of the SCR catalytic converter, and operable to mix the reductant with the flow of exhaust gas, wherein the mixer includes:
a support body defining a substantially rectangular mixing chamber in the fluid flow path, and disposed along a longitudinal axis, wherein the mixing chamber includes a lower surface, an upper surface spaced from and opposing the lower surface, a first lateral edge surface extending between the lower surface and the upper surface, and a second lateral edge surface extending between the lower surface and the upper surface and opposing the first lateral edge surface;
a plurality of first blades arranged in a single row and extending between the lower surface and the upper surface of the mixing chamber, with the single row of the first blades disposed along a transverse axis that is substantially perpendicular to the longitudinal axis;
wherein each of the first blades extends along the longitudinal axis, from an upstream edge, toward the first lateral edge surface of the mixing chamber, to a downstream edge, at a first row angle relative to the transverse axis;
a plurality of second blades arranged in a single row and extending between the lower surface and the upper surface of the mixing chamber, with the single row of the second blades disposed along the transverse axis;
wherein each of the second blades extends along the longitudinal axis, from an upstream edge, toward the second lateral edge surface of the mixing chamber, to a downstream edge, at a second row angle relative to the transverse axis;
wherein the single row of the first blades is axially spaced along the longitudinal axis from the single row of the second blades a row spacing distance; and
wherein the first row angle is less than the second row angle; and
wherein each adjacent pair of the plurality of first blades are spaced a first gap distance from each other along the transverse axis,

Assignees

• Gm Global Tech Operations Llc

Inventors

• Mital Rahul
• Yadav Anil
• Li Jianwen
• Prabhakar Amit

Classifications

• F01N13/0097

  the purifying devices are arranged in a single housing · CPC title

• F01N2240/20

  a flow director or deflector · CPC title

• F01N3/2066

  Selective catalytic reduction [SCR] · CPC title

• F01N2610/02

  the substance being ammonia or urea · CPC title

• F01N3/021

  by means of filters · CPC title